/Engine/Source/Editor/GameplayTasksEditor/Classes/K2Node_LatentGameplayTaskCall.h
Also, a K2Node_SpawnActorFromClass could not be used directly here, since we want the proxy object to implement its own BeginSpawn/FinishSpawn function (custom game logic will often be performed in the native implementation). K2Node_SpawnActorFromClass also requires a SpawnTransform be wired into it, and in most ability task cases, the spawn transform is implied or not necessary.
virtual void ExpandNode ( class [FKismetCompilerContext](API\Editor\KismetCompiler\FKismetCompilerContext) & CompilerContext, [UEdGraph](API\Runtime\Engine\EdGraph\UEdGraph) * SourceGraph )